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DOE OSTI · 3004333

Generalizable machine learning potentials for quantum-accurate predictions of non-equilibrium behavior in 2D materials

Abstract

Machine learning interatomic potentials (ML-IAPs) are emerging as transformative tools in materials modeling, promising quantum-level accuracy at a fraction of the computational cost. However, their ability to generalize beyond equilibrium configurations and to reliably capture defect- and temperature-driven behavior remains underexplored. Here, we develop and benchmark two state-of-the-art ML-IAPs, Spectral Neighbor Analysis Potential (SNAP) and Allegro, on a comprehensive dataset for monolayer MoSe₂. Using density functional theory (DFT) as the reference, we evaluate their performance in capturing stress–strain behavior, phase transition energetics, defect evolution, edge stability, and fracture toughness. Allegro, a deep equivariant neural network potential, surpasses both SNAP and the classical Tersoff potential in accuracy, efficiency, and transferability. Importantly, both ML potentials accurately reproduce experimental fracture measurements and ab initio predictions of inversion domain formation—phenomena well beyond their training sets. Our findings establish ML-IAPs as viable replacements for traditional force fields in the study of non-equilibrium mechanical phenomena, enabling large-scale, high-fidelity simulations in 2D materials and beyond. In conclusion, this work provides a broadly applicable framework for data-driven modeling of structural and functional transformations under extreme conditions.

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BibTeXRIS

Zhang, Yue [Northwestern Univ., Evanston, IL (United States)], Appleton, Robert J. [Purdue Univ., West Lafayette, IN (United States)] (ORCID:0000000211961689), Lin, Kui [The Hong Kong Polytechnic University (China)] (ORCID:0000000315263244), McCarthy, Megan Jeanne [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000343884953), Paci, Jeffrey T. [Univ. of Victoria, BC (Canada)] (ORCID:000000034341752X), Sankaranarayanan, Subramanian K.R.S. [Argonne National Laboratory (ANL), Argonne, IL (United States); Univ. of Illinois, Chicago, IL (United States)], Strachan, Alejandro [Purdue Univ., West Lafayette, IN (United States)] (ORCID:0000000241749750), Espinosa, Horacio D. [Northwestern Univ., Evanston, IL (United States)] (ORCID:0000000219073213). 2025-10-30. Generalizable machine learning potentials for quantum-accurate predictions of non-equilibrium behavior in 2D materials. https://doi.org/10.1016/j.cma.2025.118502

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